论文部分内容阅读
慈溪县的北部,分布着較大面积的盐分較重的土壤,共有面积70余万亩,約占全县土地总面积的52％。分布之广,遍及于全县各公社。面积虽大,但利用的却不多,栽培农作物的更少。这些土壤,必須逐步加以改良,把它們全部利用起来,以充分发揮它們的生产潛力。一、自然槪况和鹽土的性质慈溪县位于錢塘江下游,杭州湾的南岸。气候溫暖潮湿,年平均溫度約16℃左右,最低月分平均溫度在4-5℃之間。降雨量大,年平均雨量达1,370多毫米;地面水分蒸发也很激烈,年平均蒸发量約有1,300毫米,几乎与降雨量相等。地下水位約4.4尺左右,与海水相通,故水质頗咸。盐土結构差,毛細管作用强烈,盐分极易随着地下水分上升,使表土重新盐漬化。盐土的土壤含盐量較高,含盐量的多寡受天气晴雨的直接影响,雨时表
The northern part of Cixi County, with a larger area of the distribution of heavy salt soil, a total area of more than 70 acres, accounting for 52% of the total land area of the county. Widely distributed, throughout the county communes. Although the area is large, but not much use of cultivated crops less. These soils must be gradually improved to make full use of them to give full play to their productive potential. First, the natural conditions and the nature of salt Cixi County is located in the lower reaches of the Qiantang River, Hangzhou Bay south bank. Climate is warm and humid, the annual average temperature is about 16 ℃, the lowest month average temperature between 4-5 ℃. Large amount of rainfall, the average annual rainfall of 1,370 mm; surface evaporation is also very intense, with an average annual evaporation of about 1,300 mm, almost equal to rainfall. About 4.4 feet underground water level, and the sea connected, so the water is very salty. Saline structure is poor, capillary strong, extremely easy to salt as the groundwater increases, so that topsoil salinization. Salt soil salt content is higher, the amount of salt by the weather the direct impact of rain, rain schedule